Cold In-Place Recycling: City of Edmonton 137th Avenue – Standard General Inc.

Standard General Inc. approached the City of Edmonton during the summer of 2009 with the idea of conducting a Cold In-Place Recycling (CIR) trial using a new piece of equipment and process that would reuse the surface’s existing pavement and re-blend it into a new pavement base that would be surfaced with a 50mm asphalt overlay. A greener approach to road construction.

The City liked the idea and decided to proceed with the trial. A working partnership was created and suitable locations were identified and evaluated. The Westbound lanes of 137th Avenue; 66th Street to 82nd Street were selected by the City of Edmonton as the location for the trial. The existing pavement structure on the Arterial Roadway was 100mm of ACO asphalt overlaying 200mm of concrete road base. The Eastbound lanes had been rehabilitated using the conventional mill and overlay technique in 2009, and as such would provide a great comparison for the CIR process.

The trial was done using a Wirtgen 3800 CR Cold Recycler, which is a new type of equipment with currently only 3 available in Canada. The machine completes the recycling of the existing asphalt and application of a new overlay in one continuous process.

The Wirtgen 3800 CR Cold Recycler is a 3.8m milling machine equipped with an integrated spreading auger and paving screed. This Cold Recycler treats asphalt pavement by blending cement and bitumen emulsion or foamed bitumen with the milled recycled asphalt pavement. The milling drum granulates the existing asphalt pavement which is then mixed with binding agents and water in the machine’s milling and mixing chamber to create a new mix. This newly created mix is fed between the machine’s rear tracks and then spread and pre-compacted using a high density screed equipped with tamper bars. Once the new mix is compacted with pneumatic and vibratory rollers, it forms the base of the new pavement.

The CIR project was originally scheduled to begin in September, 2009 but was rescheduled to begin in the spring of 2010. This additional time allowed Standard General and the City of Edmonton to finalize the mix design, the construction process and the project deliverables. In late 2009, we initiated the development of a CIR / Milling division within the group and ACP Applied Products, a division of our sister company, Canadian Road Builders, was brought into the partnership with the City of Edmonton.

Under the partnership, Standard General managed the project and completed the final asphalt surfacing, ACP Applied Products then completed the grinding and recycling and we provided technical support.

Project Quantities

  • 100mm Cold In-Place Recycling 24,320 sq. metres
  • 0-50mm Cold Milling 4,485 sq.metres
  • 50mm ACO Overlay 4,115 tonnes
  • Virgin Aggregate 15%
  • Cement 0.5%
  • Liquid Asphalt 1.2%

The 137th Ave CIR project was started on May 31st and was completed on June 3rd. The roadway was opened to traffic on June 8th and the CIR surface performed very well. The quality control samples were extracted from the roadway on June 14th and the results were reported on June 16th. The overlay was started on the June 17th and was completed on June 18th.

The trial was a success and the partnership between Standard General, ACP Applied Products and the City of Edmonton went very well, hopefully providing potential for additional projects in the future.

Lear more about Standard General Edmonton by visiting the their website.